Overview
ISO 17639:2022 - "Destructive tests on welds in metallic materials - Macroscopic and microscopic examination of welds" - provides recommendations for preparing specimens, performing test procedures and reporting results for both macroscopic and microscopic examinations of welded joints. The standard defines the principle and purpose of these destructive examinations, the orientation and removal of specimens (typically transverse sections), and requirements for documenting the test and its findings.
Key Topics and Requirements
- Scope and objective: Guidance for revealing macroscopic and microscopic features of welds (grain structure, morphology, precipitates, inclusions, cracks, cavities, HAZ, etc.) and recording section shapes.
- Specimen preparation: Cutting, mounting, grinding, polishing and (where applicable) etching. Surface preparation methods should not alter the features to be examined.
- Orientation and sampling: Typical specimens are transverse to the weld axis; location, orientation and number of samples should be specified in advance (e.g., by an application standard).
- Surface finish: Level of finish depends on examination type (macro vs micro), material and documentation needs (photographs).
- Etching: Methods include immersion, swabbing and electrolytic etching; etchant type, concentration, temperature and time depend on material and examination purpose. Typical etchants are listed in ISO/TR 16060.
- Safety measures: Protective eyewear/face protection, gloves/tongs, use of fume cupboards/hoods, correct procedures for mixing acids (acid into water) and solute/solvent handling.
- Examination and assessment: Visual/optical inspection before/after etching; Table guidance indicates which defects/features are detectable by macro and micro exams.
- Designation and reporting: Standardized designation format (reference, exam type, etched/unetched, object of test, parent/weld metals, etchant) and minimum test report contents (reference, designation, specimen location/orientation, WPQR or material/consumables, etchant/method, description/photos, test date).
Applications and Users
ISO 17639:2022 is used by:
- Welding inspectors and metallurgical laboratories conducting weld testing and failure analysis
- Quality and inspection engineers validating welding procedure qualification records (WPQR)
- Fabrication, oil & gas, aerospace, power generation and construction sectors where welded joint integrity must be verified
- NDT technicians and materials scientists performing destructive weld examinations to assess cracks, lack of fusion, HAZ effects, inclusions and microstructure
Practical benefits include consistent specimen preparation, repeatable examination procedures, clearer reporting and improved comparability of metallographic results.
Related Standards
For full implementation, obtain the complete ISO 17639:2022 document from your national standards body or ISO’s website.